Oil and gas wells produce oil, gas and/or byproducts from subterranean formations. Some formations, such as shale formations, coal formations, and other tight gas formations containing natural gas, have extremely low permeability. The formation's ability to conduct resources may be increased by fracturing the formation. During a hydraulic fracture treatment, fluids are pumped under high pressure into a rock formation through a well bore to artificially fracture the formation and increase permeability and production of resources from the formation. Fracture treatments as well as production and other activities can cause complex fracture patterns to develop in the formation. Complex-fracture patterns can include complex networks of fractures that extend to the well bore, along multiple azimuths, in multiple different planes and directions, along discontinuities in rock, and in multiple regions of a reservoir.